import SwiftUI

struct UserDefaultsDemo: View {
  @AppStorage("username") private var username = ""
  var body: some View {
    VStack(spacing: 12) {
      Text(username.isEmpty ? "Hello, Guest" : "Hello, " + username)
      TextField("Username", text: $username)
        .textFieldStyle(.roundedBorder)
    }
    .padding()
  }
}

                    

import SwiftUI

struct ContentView: View {
  var body: some View {
    UserDefaultsDemo()
  }
}

                    

import SwiftUI

@main
struct MyApp: App {
  var body: some Scene {
    WindowGroup { ContentView() }
  }
}